The USB chargers on the market are diversified; however, the quality varies greatly that often causes usage problems, such as unable to charge the smart phone or tablet, damaging the battery or shortening the battery life due to unstable voltage/current, or even causing fire because of overheat during charge and resulted serious loss of human life and property. Chroma ATE Inc. with more than two decades of testing experiences in power supply field has developed a variety of Switch Mode Power Supply Auto Test Systems. Their accuracy of the tests and powerful report generation and analysis functions are the indicators of the industry beyond competition.

In recent days, the network spreads that the tablet produced by company A is unable to charge when connecting to the USB port on PC as the rated current of USB port is insufficient. In addition, there are news reported that the smart phone has to be charged by the charger of its own brand as the quality of non-original white box mobile charger is poor. But is it really true? In fact, to ensure the safety of handheld mobile devices and the internal battery life, more and more brand manufacturers have designed the charger identification function on their mobile devices. Therefore, no current is provided to charge the mobile device unless the own brand or recognized charger is used. Currently the identification of charger mainly utilizes the voltage range of D+/D- pin on the USB port as the figure shown below; and changing the resistance can set the mobile device to identify the V_D-,V_D+ voltage on the charger. This could set off the application revolution of USB that is to enforce adding ID for identification in the regulation to improve the circuit protection function when implementing the high power charge on USB-PD.

To keep abreast of the times, Chroma ATE Inc. has developed the UUT (Unit Under Test) ID pin signal measurement test items specialized for this identification function on the Auto Test System. For the existing customers of Chroma, additional DMM such as Model 12061 6 1/2 Digits Digital Multimeter is purchased for Chroma ATS, the service center of Chroma will integrate the ID pin signal measurement test items into the test system.